I wouldn’t even say startups here! I think you’ll find it’s people with social-media ‘sense’ who are nimble like you said.
That then turns into a business after being successful. Then they die, because they never factor in what’s beyond the horizon.
I’ve managed two of these ‘waves’ so far, and I could see the external link one coming from a mile away. It was just obvious looking at statistics, and the people themselves.
Damn good write up, mate.